The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Worthington you can determine when you can plant sweet potatos by looking at the USDA zone info.

Planting Calendar for Sweet Potatos

Frost tolerance for sweet potatos:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

You should not plant sweet potatos until after the last frost when the weather gets warmer because they are not cold tolerant.

The earliest that you can plant sweet potatos in Worthington is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant sweet potatos and expect a good harvest is probably August. If you wait any later than that and your sweet potatos may not have a chance to grow to maturity. If you are starting your sweet potatos indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Worthington. In the coldest months of winter you can expect an average low temperature of -25°F.

Remember that USDA zone info for Worthington may not be accurate from year to year and the actual date of last frost is different every year. Half of the time in Worthington it frosts late in the year after May 15 so always be ready to cover your sweet potatos if you have a surprise late frost.

USDA Zone Info for Worthington

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Worthington

You may be interested in your other planting guides for Worthington.